Fl4m3Ph03n1x

Fl4m3Ph03n1x

Gradient does not recognize type of TypedStruct structures

Background

I have a module that uses TypedStruct to create structs. This is the code:

defmodule Shared.Data.Authorization do
  @moduledoc """
  Saves authorization details for a user. It also contains other details.
  """

  use TypedStruct

  alias Shared.Utils.Structs

  @type authorization :: %{
          (cookie :: String.t()) => String.t(),
          (token :: String.t()) => String.t()
        }

  @derive Jason.Encoder
  typedstruct enforce: true do
    @typedoc "Authorization information for a user"

    field(:cookie, String.t())
    field(:token, String.t())
  end

  @spec new(authorization()) :: __MODULE__.t()
  def new(%{"cookie" => cookie, "token" => token} = auth)
      when is_binary(cookie) and is_binary(token) do
    Structs.string_map_to_struct(auth, __MODULE__)
  end
end

The problem here is that Gradient does not seem to understand that t() is created, so it errors out:

 lib/data/authorization.ex: The function call on line 26 is expected to have type t() but it has type struct()
 24   def new(%{"cookie" => cookie, "token" => token} = auth)
 25       when is_binary(cookie) and is_binary(token) do
 26     Structs.string_map_to_struct(auth, __MODULE__)
 27   end

For additional context, here is the string_map_to_struct code:

  @spec string_map_to_struct(map, module | struct) :: struct
  def string_map_to_struct(data, target_struct) do
    data
    |> Morphix.atomorphiform!() # string_map to atom_map
    |> data_to_struct(target_struct)
  end

  @spec data_to_struct(Enumerable.t(), module | struct) :: struct
  def data_to_struct(data, target_struct), do: struct(target_struct, data)

Temporary fix

I decided to convert that code into its native form using defstruct:

defmodule Shared.Data.Authorization do
  @moduledoc """
  Saves authorization details for a user. It also contains other details.
  """

  alias Shared.Utils.Structs

  @enforce_keys [:cookie, :token]
  defstruct [:cookie, :token]

  @type authorization :: %{
          (cookie :: String.t()) => String.t(),
          (token :: String.t()) => String.t()
        }

  @typedoc "Authorization information for a user"
  @type t() :: %__MODULE__{
          cookie: String.t(),
          token: String.t()
        }

  @spec new(authorization()) :: t()
  def new(%{"cookie" => cookie, "token" => token} = auth)
      when is_binary(cookie) and is_binary(token) do
    Structs.string_map_to_struct(auth, __MODULE__)
  end
end

Gradient does not complain here.

Question

Is there a fix for this?
(other than removing typed struct?)

Most Liked

mafinar

mafinar

It’s cool that you also raised issue here: Gradient does not recognize type of TypedStruct structures · Issue #165 · esl/gradient · GitHub I am adding this as comment so that anyone coming to this post can go and follow the progress there. I myself am interested in this one. Thanks.

Fl4m3Ph03n1x

Fl4m3Ph03n1x

I usually update both threads if/when the issue is solved, so I got you covered there :stuck_out_tongue:

Where Next?

Popular Backend topics Top

Jsdr3398
I’m trying to create a router where everything is in a collection of routes (similar to how I do my routes in expressjs). But it doesn’t ...
New
New
JimmyCarterSon
I am following this tutorial . I have followed carefully correcting errors as I go. The app allows you to create a blog post and add comm...
New
Fl4m3Ph03n1x
Background I am trying to find a cheap and easy way to create New Types in Elixir, and Records seem to be just what I would need. Probl...
New
JimmyCarterSon
I am confused about the Schema setup, I am setting up a new application and I want to seed files in it as well. I tried to mix to create...
New
Fl4m3Ph03n1x
Background I am moving towards defined data structures in my application, and I find that TypedStruct is quite useful. Questions Howeve...
New
Fl4m3Ph03n1x
Background I am a fan of dialyzer and friends (looking at Gradient) and I try to have sepcs in my code as much as I can. To this end, I a...
New
pillaiindu
Currently reading the book “Programming Phoenix LiveView”. At the end of the Chapter 1, I’m trying to solve the guess game. If the user ...
New
pillaiindu
What is the difference between using :references and :belongs_to in the following command? bin/rails generate scaffold LineItem product:...
New
Fl4m3Ph03n1x
Background As I often do, I read books to learn and improve myself. I also enjoy teaching and helping others when I can, so this is somet...
New

Other popular topics Top

malloryerik
Any thoughts on Svelte? Svelte is a radical new approach to building user interfaces. Whereas traditional frameworks like React and Vue...
New
wolf4earth
@AstonJ prompted me to open this topic after I mentioned in the lockdown thread how I started to do a lot more for my fitness. https://f...
New
AstonJ
There’s a whole world of custom keycaps out there that I didn’t know existed! Check out all of our Keycaps threads here: https://forum....
New
AstonJ
Just done a fresh install of macOS Big Sur and on installing Erlang I am getting: asdf install erlang 23.1.2 Configure failed. checking ...
New
AstonJ
I ended up cancelling my Moonlander order as I think it’s just going to be a bit too bulky for me. I think the Planck and the Preonic (o...
New
Rainer
Not sure if following fits exactly this thread, or if we should have a hobby thread… For many years I’m designing and building model air...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
gagan7995
API 4 Path: /user/following/ Method: GET Description: Returns the list of all names of people whom the user follows Response [ { ...
New
New
New